Noun, referring to any object meant to attach to one's keys.
These are ordinarily sold as decorative
tchotchkes so people who can't afford the other designer stuff can at least have designer keys. Sold by designers such as
DKNY,
Coach, CK,
Gucci, etc. Also sold heavily in
souvenir shops and
novelty stores, where they say cute/lame things or loudly proclaim where you spent your Spring Break.
Interestingly, this word is used extensively by retailers, but neither "keyfob" nor "key fob" are in any of the several dictionaries I've checked, including
Merriam-Webster.